The disclosure of the following priority application is herein incorporated by reference: Japanese Patent Application No. 2001-007841 filed Jan. 16, 2001.
1. Field of the Invention
The present invention relates to a range finder using beam light such as a laser and, in particular, relates to a range finder capable of measuring a separation between two target objects.
2. Description of Related Art
The current range finder is composed of a light emitting device for emitting a laser beam such as a laser diode, an objective lens for irradiating an object to be measured with the light emitted from the light emitting device, a detector for detecting the light reflected from the object to be measured via a receiving lens, and a measuring part for measuring the distance to the object on the basis of the reflected light detected by the detector.
The range finder irradiates the object to be measured by the laser beam, detects the reflected light from the object to be measured, and measures the distance to the object by measuring the time interval between the emission of the laser beam and the detection of the reflected light.
However, the range finder has not been able to measure the separation between two targets, nor the height of a target.
The present invention is made in view of the aforementioned problem and has an object to provide a range finder including a light source for emitting a light beam to an object to be measured, a detector for detecting a reflected light from the object, a measuring part for calculating the distance to the object on the basis of the reflected light detected by the detector, a display capable of displaying two objects to be measured as well as the distance to the object measured by the measuring part, a finder for observing the two objects shown on the display, at least one index set on the display for indicating the positions regarding the two objects shown on the display, a field angle setting portion, equipped with a moving part for moving the index to the position of the object, for setting a field angle between the two objects on the basis of the positions indicated by the index, and a calculating part for calculating the separation between the two objects on the basis of the distance to the object measured by the measuring part and the field angle set by the field angle setting portion.
The two objects can be observed through the finder, and the separation between the two objects can be calculated on the basis of the field angle relative to the two objects set by the field angle setting portion and the distance to the object calculated by the measuring part.
In one preferred embodiment of the present invention, the number of the index is two, and the separation between the two indexes can be variable in accordance with the separation between the two objects.
In one preferred embodiment of the present invention, the moving part in the field angle setting portion is a rotating ring set on the finder.
In one preferred embodiment of the present invention, the field angle setting portion includes a potentiometer for detecting a rotating angle of the rotating ring, and an angle calculating circuit for calculating the field angle on the basis of the detected result of the potentiometer.
In one preferred embodiment of the present invention, the index indicates the position of the object by a contrast between a clear part and a dark part.
In one preferred embodiment of the present invention, the range finder further includes a memory for storing the separation between the two objects calculated by the calculating part.
In one preferred embodiment of the present invention, the display shows the separation between the two objects in an area other than the area where the distance to the object is shown.
According to another aspect of the present invention, a range finder including a light source for emitting a light beam to an object to be measured, a detector for detecting a reflected light from the object, a measuring part for calculating the distance to the object on the basis of the reflected light detected by the detector, a display capable of displaying two objects to be measured as well as the distance to the object measured by the measuring part, a finder for observing the two objects shown on the display, at least one index set on the display for indicating the positions regarding the two objects shown on the display, a field angle setting portion, equipped with a moving part for moving the index to the position of the object, for setting a field angle between the two objects on the basis of the positions indicated by the index, a calculating part for calculating the separation between the two objects on the basis of the distance to the object measured by the measuring part and the field angle set by the field angle setting portion, a power-measurement switch for inputting power supply and for carrying out measurement, and a mode switch for changing mode to the separation measuring mode.